Epi Administration Research Articles

Low-Dose Treatment with Epirubicin, a Novel Histone Deacetylase 1 Inhibitor, Exerts Anti-leukemic Effects by Inducing Ferroptosis

AimsLeukemia is hematopoietic stem cell malignant tumor with poor outcomes. Histone deacetylase 1 (HDAC1) is highly expressed in leukemia and current HDAC1 inhibitors have clinical limitations in leukemia therapy. Therefore, novel HDAC1 inhibitor is imperative to being found and its mechanism needs to be further explored. Materials and methodsNovel HDAC1 inhibitors were discovered through drug virtual screening. CCK-8, EdU and soft agar assay were used to assess the anti-leukemic effect of the candidate HDAC1 inhibitor. ROS, lipid peroxidation, intracellular Fe2+ and LIP assay were employed to verify cell ferroptosis. Additionally, a xenograft model was performed to explore the efficacy and safety of candidate HDAC1 inhibitor in vivo. ResultsHDAC1 might be a promising therapeutic target for leukemia and Epirubicin (Epi) could be used as a potential HDAC1 inhibitor. Low-dose Epi exhibited good anti-leukemic effects by inhibiting cell proliferation, DNA synthesis and colony formation. Low-dose Epi could induce ferroptosis by triggering lipid peroxidation, which was better than that treated with current HDAC1 inhibitors Chidamide or Vorinostat, ROS generation and Fe2+ overload in leukemia cells. Mechanistically, low-dose Epi induced ferroptosis by targeting amino acid metabolism and iron metabolism. Similar results were found in a xenograft model in NOG mice with a good safety profile. ConclusionOur study demonstrated that Epi might be used as a HDAC1 inhibitor. Low-dose Epi could inhibit tumor progression by inducing cell ferroptosis in vitro and in vivo. Thus, Epi administration with lower concentration may be much more favorable and safer in the treatment with leukemia.

(-)-Epicatechin treatment modify the expression of genes related to atrophy in gastrocnemius muscle of male rats obese by programing.

The aim of this study is to determine if the offspring of mothers with obesity, present disorders in the expression of genes related to atrophy or protein synthesis in the muscle and if these disorders are modified with the (-)-epicatechin (Epi) treatment. Six male offspring per group were randomly assigned to the control groups [C and offspring of maternal obesity (MO)] or the Epi intervention groups, Epi treatment for 13 weeks (C + Epi long or MO + Epi long), or Epi administration for two weeks (C + Epi short or MO + Epi short). The effect of Epi in the gastrocnemius tissue was evaluated, analyzing mRNA and protein levels of Murf1, MAFbx, Foxo1, NFkB, and p70S6K-alpha. After the analysis by two-way ANOVA, we found an influence of the Epi long treatment over the model, by decreasing the Murf1 gene expression in both groups treated with the flavonoid (C + Epi long and MO + Epi long) (p = 0.036). Besides, Epi long treatment over the NFκB expression, by decreasing the fold increase in both groups treated with the flavonoid (C + Epi long and MO + Epi long) (p = 0.038). We not find any interaction between the variables or changes in the MAFbx, Foxo1 mRNA, neither in the phosphorylated/total protein ratio of NFκB, Foxo1, or p70S6K-alpha. In conclusions, treatment with a long protocol of Epi, reduces the mRNA of the muscle atrophy genes Murf 1 and NFkB, in the gastrocnemius muscle; however, these changes are not maintained at protein level.

(-)-Epicatechin improves body composition of male rats descendant of obese mothers postnatally fed with a high-fat diet.

A combination of maternal obesity and high-fat diet (HFD) in offspring postnatal life has deleterious effects, and (-)-epicatechin (Epi) treatment can reverse these adverse effects. To investigate whether Epi administration can modify fat mass, muscle mass, and bone mass in male rats descended from obese mothers, fed postnatally on an HFD. Male offspring of mothers fed with control diet formed the control group (C), control group with high-fat diet (CHF), and control group with high-fat diet + epicatechin (CHF + Epi). Male offspring of maternal obesity formed the group with control diet (MO), maternal obesity group with high-fat diet (MOHF), and maternal obesity group with high-fat diet + epicatechin (MOHF + Epi). We measured total fat and weight of visceral adipose tissue by dissection and by dual-energy x-ray absorptiometry scanning body composition. Epicatechin diminished total and visceral pads fat of male offspring of CHF + Epi and MOHF + Epi groups versus to male offspring of CHF and MOHF groups. Besides, epicatechin increased lean mass in CHF + Epi and MOHF + Epi groups, but these changes were not significant. Total body mineral density of the male offspring of CHF, MOHF, and MOHF + Epi groups was significantly higher versus male offspring of C and MO groups. Obesity programming model plus a high-fat postnatal diet presents higher visceral adipose tissue, decreased lean mass, and modified body mineral density when compared with a direct obesity model and its controls. Epicatechin treatment improved body composition; however, it was not able to induce similar values as presented by the controls.

Epinephrine May Contribute to the Persistence of Traumatic Memories in a Post-traumatic Stress Disorder Animal Model.

The importance of catecholamines in post-traumatic stress disorder (PTSD) still needs to be explored. We aimed to evaluate epinephrine’s (EPI) causal role and molecular mechanism for the persistence of PTSD traumatic memories. Wild-type (WT) and EPI-deficient mice (phenylethanolamine-N-methyltransferase-knockout mice, Pnmt-KO) were induced with PTSD and behavioral tests were performed. Some Pnmt-KO mice were administered with EPI or vehicle. Catecholamines were quantified by HPLC-ED. Nr4a1, Nr4a2, and Nr4a3 mRNA expression were evaluated by real-time PCR in hippocampus samples. It was observed an increase in EPI and freezing behavior, and a decrease in open arm entries in the elevated plus-maze test and time spent in the light in the light–dark test in WT mice in the PTSD-induction group compared to control. After induction of PTSD, Pnmt-KO mice showed a decrease in freezing, as well as an increase in open arm entries and transitions between compartments compared to WT. After PTSD induction, Pnmt-KO mice administered with EPI showed an increase in freezing compared with the vehicle. On day 0 of PTSD induction, it was observed an increase in mRNA expression of Nr4a2 and Nr4a3 genes in the hippocampus of WT mice compared to control, contrary to Pnmt-KO mice. In conclusion, our data suggest that EPI may be involved in the persistence of traumatic memories in PTSD, possibly through enhancement of the expression of Nr4a2 and Nr4a3 genes in the hippocampus. Peripheral administration of EPI restored contextual traumatic memories in Pnmt-KO mice, which suggests a causal role for EPI. The persistence of contextual traumatic memories may contribute to anxiety-like behavior and resistance of traumatic memory extinction in this PTSD mice model.

Effects of Ovariectomy on Skeletal Muscle Structure and Function in Young Female Rats: Protective Effects of the Flavanol (−)‐Epicatechin

BackgroundMenopausal women suffer from various symptoms due to estrogen deficiency. Menopause can occur as a natural progression of aging or following the surgical removal of the ovaries or their damage from treatments such as chemotherapy. In women, estrogens are known to play a key role in regulating metabolism, cardiovascular, brain and bone structure and function amongst other organs and systems. However, little is known about the impact that low estrogen levels have on skeletal muscle structure and function. The flavanol (−)‐epicatechin (Epi; which is present in large concentrations in cacao) decreases muscle fatigue and promotes skeletal muscle growth in animal models. In clinical studies, the administration of cocoa and/or Epi can (in normal subjects) enhance muscle function while limiting the organ damage seen in Becker or Duchenne muscular dystrophy patients.ObjectiveThis study aims to characterize the long‐term effects of ovarian hormone depletion on skeletal muscle (macro and microscopic) structure and function. We also wish to explore the capacity of Epi treatment to reverse the loss induced by hormone depletion in muscle mass and function.MethodsThree month old female Wistar rats were used for the experiments (n=30). Animals were allocated into 3 groups: 1) sham, 2) ovariectomized (OVX, provided water by daily gavage) and, 3) OVX plus Epi treatment (provided Epi daily by oral gavage at 1 mg/kg/day dissolved in water). Once animals were allocated into their groups, they were subjected to surgery and allowed to recover for 1 week before gavage was initiated. Over the course of 3 months, the estrous cycle, body weight, and food intake of the rats was monitored. Animals were also subjected to treadmill and front limb strength testing. At the time of euthanasia, the gastrocnemius and EDL muscle were collected as well as blood samples for biochemical and/or histological analysis.ResultsAfter 3 month of ovariectomy, rats developed significant decreases in skeletal muscle mass, loss of front limb strength (~15%) and endurance as measured by treadmill testing (~50%). Histology analysis of gastrocnemius samples demonstrated significant decreases in myofiber cross sectional area. The analysis of skeletal muscle samples by Western blots also demonstrated significant increases in the content of atrophy pathway associated proteins (MURF, ATF1, atrogin) (~30%). In blood, significant increases in circulating levels of the proinflammatory cytokines occurred (~50%). Three week of treatment with Epi was able to fully restore the loss of muscle mass. Within1 week of treatment a recovery of front limb strength was noted to occur. Terminal treadmill testing also demonstrated a full recovery of exercise capacity of ovariectomized rats treated with Epi.ConclusionsIn this study we demonstrate the significant adverse impact that reductions in ovarian hormones play on skeletal muscle structure and function. Most strikingly, Epi was able to fully reverse the deleterious effects of ovariectomy. Of interest is that Epi has been provided safely to humans and evidence protective and/or beneficial effects on muscle structure and function.

Glucose Levels during the First 24 Hours following Perinatal Hypoxia.

Hypoglycemia is a significant risk factor for perinatal brain injury and adverse outcomes, particularly in infants requiring resuscitation following hypoxic ischemic (HI) insult. We aimed to study blood glucose (BG) levels in physiologically stressed infants in the presence or absence of epinephrine (Epi) administration at resuscitation in the first 24 hours after birth. A retrospective chart review of all infants with heart rate (HR) < 100/min at 1 minute requiring positive pressure ventilation (PPV) at birth was performed. Infants were classified into two groups as follows: (1) PPV group: infants' HR improved with PPV only at resuscitation, and Epi group: infants received Epi at resuscitation for persistent bradycardia. Serial measurements of BG levels collected and glucose infusion rate (GIR) calculated at 24 hours. By design, infants in the Epi group had lower cord pH and higher base deficit. BG was significantly lower overtime in premature infants ≤32 weeks of gestation in the Epi group. The BG was markedly higher in near-term and term infants in the Epi group compared with the PPV group. Hypoglycemia was more common despite administration of higher GIR in premature infants ≤32 weeks of gestation. In the presence of physiological stress, premature infants are more at risk for hypoglycemia than term infants.

(-)-Epicatechin reduces adiposity in male offspring of obese rats.

To determine whether (-)-epicatechin (Epi) could decrease visceral adipose tissue and improve the metabolic profile of male offspring rats, after maternal obesity was induced by a high-fat diet (HFD). Maternal obesity in albino Wistar rats was induced with a HFD, whereas male offspring were fed with chow diet throughout the study. Eight male offspring per group, from different litters, were randomly assigned to the experimental or to the control groups. In the experimental group, Epi was administered at a dose of 1 mg/kg of body weight to the male offspring twice daily for two weeks, beginning at postnatal day (PND). Weight of visceral adipose tissue, adipocyte size, and several metabolic parameters. Epi administration in the male offspring induced a significant decrease in the amount of visceral fat (11.61 g less, P < 0.05) and in the size of adipose cells (28% smaller, P < 0.01). Besides, Epi was able to decrease insulin, leptin, and Homeostasis Model Assessment -Insulin Resistance (HOMA-IR) (P < 0.05), as well as triglycerides, when the experimental group was compared to the untreated male offspring of obese rats (P < 0.01). Epi administration can reverse the negative effects that maternal obesity has on the male offspring. This could be because Epi reduces the amount of visceral fat and improves metabolic profile.

(−)-Epicatechin modifies body composition of the male offspring of obese rats

Abstract The aim of our study was to determine if two protocols of (−)-epicatechin (Epi) (short and long) can modify fat, muscle and bone mass, in the male offspring of the maternal rat obesity model induced by high-fat diet (HFD). Four male offspring per group from different litters were randomly selected to the control or Epi intervention groups. We administered Epi twice daily/13 weeks (long) or for two weeks (short). The long Epi administration induced a significant decrease in the amount of total and visceral fat and an increased lean mass. Besides, short Epi administration increased whole body BMD of the male offspring of the control and maternal obesity groups. In conclusion, the administration of long Epi protocol elicited better results in decreasing total fat and all fat deposits and increased lean mass. However, only the short Epi protocol increased the total BMD in the male offspring.

Abstract 239: Frequency of Advanced Cardiac Life Support Medication Use and Association With Survival During In-Hospital Cardiac Arrest

Introduction: Resuscitation medication shortages are widespread across the US. We sought to determine the frequency and quantity of meds used during IHCA. Methods: Retrospective, single center, chart review at a large, urban teaching hospital. Adults over 18 who suffered IHCA between Jan 2017 and Mar 2018 were identified. Trained and supervised research assistants used a standardized data tool to extract data from the EMR. Primary outcome was the frequency and quantity of ACLS meds used during IHCA. Secondary outcomes included evaluating the association of med administration with ROSC and survival as well as the use of sodium bicarb with survival in patients with pre-existing end stage renal disease. Results: Criteria were met for 181 IHCA events. Demographics: 71% (128 of 181) black; mean age 65; and 46% (83 of 181) women. Epi was given in 86.7% (157 of 181) cases, with average cumulative dose of 4.2 mg, sodium bicarb given in 63.5% (115 of 181), average dose of 1.9 amps, calcium chloride given in 39.2% (71 of 181), average dose of 1.9 amps, amiodarone was given in 30.9% (56 of 181), average dose of 311.8 mg, and atropine was given in 13.8% (25 of 181), average dose of 1.3 amps. Administration of sodium bicarb was associated with lower rates of ROSC (OR 0.31, 95% CI 0.18 to 0.83) and lower survival (OR 0.31, 95% CI 0.13 to 0.73). Administration of mag sulfate was associated with lower rates of ROSC (OR 0.33, 95% CI 0.13 to 0.83), but no difference in survival (OR 0.34, 95% CI 0.10 to 1.14). Administration of epi, amiodarone, calcium, dextrose, or atropine was not associated with a change in rates of ROSC or survival. In patients with pre-existing ESRD (45 of 181), 73.3% (33 of 45) received sodium bicarb, with 51.5% (17 of 33) achieving ROSC, and 12.1% (4 of 33) surviving to discharge. In patients without ESRD (136 of 181), 60.3% (82 of 136) received sodium bicarb, with 65.9% (54/82) achieving ROSC, and 22.0% (18 of 82) surviving to discharge. (12.1% vs 22.0% p = 0.224). Conclusions: Substantial amounts of drugs with known recent shortage are used in IHCA with no significant increase in ROSC or survival to discharge. Administration of sodium bicarb during IHCA is associated with lower rates of ROSC and survival. These results may be due to confounders such as code duration.

Abstract 262: Hemodynamically-Guided Optimum Chest Compression Point in a Rat Model of Cardiopulmonary Resuscitation

Introduction: CPR aims to re-establish blood flow by chest compression (CC), achieving threshold levels of coronary perfusion pressure (CPP). For this, current guidelines recommend the lower sternal half as optimum CC point. However, this point might be not optimal for every individual. We investigated the hemodynamics generated by CC performed on different chest points in a rat model of CPR. We hypothesized that a CC point hemodynamically-identified would be a better approach compared to the lower sternal half. Methods: Ten male rats were anesthetized and arterial and right atrial pressures monitored. Ventricular fibrillation was induced and untreated for 8 min. CPR, including mechanical CC, ventilation, and epinephrine, was then performed for 8 min. Animals were divided to receive CC performed either on the lower sternal half (standard (STD), n=5) or on an optimum point identified as the one able to generate the maximum CPP (MaxCPP group, n=5). Cardiac districts involved in CC were subsequently identified by computed tomography (CT). Results: STD CC produced a CPP that was constantly below the threshold for successful resuscitation and trended to decrease over time. When the optimum CC point was identified hemodynamically, the CPP generated was constantly &gt; 20 mmHg. Indeed, CPP was significantly higher in the MaxCPP group compared to the STD one for the whole 8 min of CPR (p&lt;0.01, Fig). Moreover, administration of epi rapidly further improved CPP (p&lt;0.01 vs. pre-epi) in the group with an optimized CC point, while no drug effect was observed in the STD one. CT scan showed that the lower sternal half did not correspond to the LV maximum diameter, known to account for a maximum stroke volume generation during CC (Fig). Conclusion: Standard lower sternal half CC point is not able to maximize hemodynamics during CPR, making ineffective CC efforts and vasopressor administration. The quality of CPR may improve if the optimum CC point is identified as a reflection of CPP generated.

Epinephrine use in older patients with anaphylaxis: Clinical outcomes and cardiovascular complications

BackgroundThere is little data describing the differences in epinephrine (epi) administration and cardiac complications among older and younger patients with anaphylaxis. MethodsThis retrospective cohort study was conducted at two urban emergency departments (ED) over a 5 year-period, and included adults who met a pre-specified criteria for anaphylaxis. Patients ≥50years of age were defined as “older”. Univariate logistic regression was performed to compare the difference in frequency of epi administration between the “older” and “younger” groups. Among those who received epi, the proportion of patients who received doses exceeding the recommended maximum and who had pre-specified cardiovascular complications were compared between the two groups, stratified further by route of administration. ResultsOf 2995 allergy-related visits, 492 met criteria for anaphylaxis, including 122 (24.8%) older patients. Older patients were less likely to receive epi injection (36.1% vs. 60.5%). Of those who received epi, older patients were more likely to receive excessive dose of epi (7/44, 15.9% vs 2/225, 0.9%, unadjusted OR 20.7, 95% CI 3.8–211.7). Four (4/44, 9.1%) older patients experienced cardiovascular complications, compared to 1/225 (0.4%) in the younger group (unadjusted OR 22.4, 95% CI 2.1–1129.8). When examining only intra-muscular epinephrine, 1/31 older patients had cardiac complications, compared to 1/186 in the younger group. ConclusionOlder patients with anaphylaxis were less likely to receive epi injection. Intramuscular epi appears safe in this population; however, the use of intravenous epi should be avoided in older patients due to the potential of developing serious cardiac complications.

Improvement and Application of Acute Blood Stasis Rat Model Aligned with the 3Rs (Reduction, Refinement and Replacement) of Humane Animal Experimentation.

To establish a novel cardiocentesis method for withdrawing venous blood from the right atrium, and to improve an acute blood stasis rat model using an ice bath and epinephrine hydrochloride (Epi) while considering the 3Rs (reduction, refinement, and replacement) of humane animal experimentation. An acute blood stasis model was established in male Sprague-Dawley rats by subcutaneous injection (s.c.) Epi (1.2 mg/kg) administration at 0 h, followed by a 5-min exposure to an ice-bath at 2 h and s.c. Epi administration at 4 h. Control rats received physiological saline. Rats were fasted overnight and treated with Angelicae Sinensis Lateralis Radix (ASLR) and Pheretima the following day. Venous blood was collected using our novel cardiocentesis method and used to test whole blood viscosity (WBV), prothrombin time (PT), activated partial thromboplastin time (APTT), and fibrinogen (FIB) content. The rats survived the novel cardiocentesis technique; WBV value returned to normal while hematological parameters such as hemoglobin level and red blood cell count were restored to >94% of the corresponding values in normal rats following a 14-day recovery. Epi (1.2 mg/kg, s.c.) combined with a 5-min exposure to the ice bath replicated the acute blood stasis rat model and was associated with the highest WBV value. In rats showing acute blood stasis, ASLR treatment [4 g/(kg·d) for 8 days] decreased WBV by 9.98%, 11.09%, 9.34%, 9.00%, 7.66%, and 7.03% (P<0.05), while Pheretima treatment [2.6 g/(kg·d), for 8 days] decreased WBV by 25.49%, 25.94%, 16.28%, 17.76%, 11.07%, and 7.89% (P<0.01) at shear rates of 1, 3, 10, 30, 100, and 180 s-1, respectively. Furthermore, Pheretima treatment increased APTT significantly (P<0.01). We presented a stable, reproducible, and improved acute blood stasis rat model, which could be applied to screen drugs for promoting blood circulation and eliminating blood stasis.

Recovery of Indicators of Mitochondrial Biogenesis, Oxidative Stress, and Aging With (-)-Epicatechin in Senile Mice.

There is evidence implicating oxidative stress (OS) as the cause of the deleterious effects of aging. In this study, we evaluated the capacity of the flavanol (-)-epicatechin (Epi) to reduce aging-induced OS and restore mitochondrial biogenesis, as well as, structural and functional endpoints in aged mice. Senile (S; 26-month-old) C57BL/6 male mice were randomly assigned to receive either water (vehicle) or 1mg/kg of Epi via oral gavage (twice daily) for 15 days. Young (Y; 6-month-old) mice were used as controls. In S brain, kidney, heart, and skeletal muscle (compared with Y animals) an increase in OS was observed as evidenced by increased protein-free carbonyls and decreased reduced glutathione levels as well as sirtuin 3, superoxide dismutase 2, catalase, thioredoxin and glutathione peroxidase protein levels. Well-recognized factors (eg, sirtuin 1) that regulate mitochondrial biogenesis and mitochondrial structure- and/or function-related endpoints (eg, mitofilin and citrate synthase) protein levels were also reduced in S organs. In contrast, the aging biomarker senescence-associated β-galactosidase was increased in S compared with Y animals, and Epi administration reduced levels towards those observed in Y animals. Altogether, these data suggest that Epi is capable of shifting the biology of S mice towards that of Y animals.

Administration of glucagon and epinephrine during cardiopulmonary resuscitation improves hemodynamics and survival in a swine model of prolonged ventricular fibrillation

coronary perfusion pressure (CPP) calculated. CBF was continuously monitored by a transonic flow probe. VF was electrically induced andPEAproducedbydelivering electrical countershock(s). CPR, including mechanical chest compression and ventilation, was then initiated and continued for 15min. Epi (20 g/kg) was administered into the right atrium after 2min of CPR and repeated every 3min thereafter. If animals were resuscitated, the study sequence was repeated after 30min of recovery. Results: A total of 19 experimental cycles were completed with a mean of 2±1 cycles/pig. CPP significantly increased from 14±6mmHg before epi to a peak of 32±13mmHg (p<0.01) at 1min after epi administration. Concurrent with CPP increases, CBF decreased from 46±19mL/min before epi to the lowest value of 22±18mL/min (p<0.01) at 30 s after epi (Fig. 1). Both increase in CPP and decrease in CBF persisted beyond 3min after epi. However, while CPP already decreased to 24±12mmHg, CBF persisted with a low flow of 25±12mL/min 3min after epi. Conclusions: In this model, administration of epi significantly increased CPP during CPR. Increases in CPP, however, were not accompanied by increases in CBF, which was markedly reduced following epi.

Rapid epinephrine administration improves early outcomes in out-of-hospital cardiac arrest

IntroductionEarly administration of epinephrine (Epi) improves outcomes in animal models of cardiac arrest, but there is limited time-dependent clinical data regarding its benefit. ObjectiveOur objective was to assess whether timing of Epi administration was associated with improved outcomes after out of hospital cardiac arrest (OHCA). MethodsWe performed a retrospective analysis of a cardiac arrest database from a suburban EMS system from November 2005 to April 2011. Data was abstracted from EMS run sheets, including drug treatment, route and timing of drug administration, and other Utstein variables. Our primary outcome was return of spontaneous circulation (ROSC). Secondary outcomes measured were survival to hospital admission and discharge. For analysis, data were dichotomized according to timing of Epi administration: early Epi group (defined as 911 call to Epi administration of ≤10min) and late Epi group (>10min). Further, exploratory analyses were conducted looking at subgroups sorted by initial rhythm and whether the arrest was witnessed. Wilcoxon rank sum tests, chi-square tests, 95% confidence intervals, and multi-variable regression were used for statistical analysis. ResultsWe reviewed 809 patients from study communities: 123 patients were excluded, leaving a sample size of 686 for study analysis. The mean time from 911-Epi was 14.3±5.5min, with 155 (22.6%) receiving early Epi. Key arrest and treatment characteristics were similar between groups. Patients who received early Epi were more likely to have ROSC (32.9% vs. 23.4%, OR 1.59 (1.07, 2.38)), however, no significant increase in survival to admission or discharge was observed. Patients with an initial rhythm of PEA had an increased rate of ROSC (48.6% vs. 21.5%, OR 3.45 (1.56, 7.62)) but not survival to discharge (5.9% vs. 2.6%), OR 2.35 (0.38, 14.7) with early Epi. In a multivariable analysis of bystander witnessed arrests, early Epi was associated with a higher rate of ROSC (OR 3.20 (1.75, 5.88) but not survival to discharge (OR 1.48 (0.50, 4.36)). No improvement in ROSC or secondary outcomes was noted in patients with other arrest rhythms or un-witnessed arrest with Early Epi. ConclusionsWithin the limitations of our study, this data suggests improved rates of ROSC with early Epi administration during OHCA resuscitation, but this study lacks adequate sample size to demonstrate impact on survival to discharge. Large prospective trials are needed to further delineate the benefit of early Epi administration in OHCA.

Effects of RNA interference-mediated NRP-1 silencing on the proliferation and apoptosis of breast cancer cells.

Lentiviral expression vectors carrying human NRP-1 short hairpin RNA (shRNA) were constructed and selected to present highly efficient NRP-1/shRNA interference sequences, in order to investigate the effects of RNA interference (RNAi)-mediated NRP-1 silencing on the biological activities of breast cancer cells. Three pairs of human NRP-1 targeted specific interference sequences and one pair of non-specific control sequences were designed, synthesized and subcloned into pLB lentiviral vectors, which were further identified by polymerase chain reaction (PCR) and sequencing. Recombinant and lentiviral packaging plasmids were co-transfected into 293FT cell lines in order to produce lentiviral particles and to infect breast cancer cells with high NRP-1 expression. Flow cytometry was used to sort green fluorescent protein-positive cells. Fluorescence quantitative-reverse transcription-PCR and western blot analysis were employed to identify the interference silencing sequence with the most efficient silencing profile. A cell counting kit-8 assay and an Annexin V-propidium iodide method in combination with flow cytometry were used to examine the effects of RNA interference-mediated NRP-1 gene silencing on cell proliferation, apoptosis and sensitivity to chemotherapy. The recombinant lentiviral plasmid pLB-NRP-1/shRNA was constructed successfully, as confirmed by PCR and sequencing. After the infection of recombinant lentiviral plasmids, the expression profiles of NRP-1 mRNA, and proteins of MCF-7 and SK-BR-3 cell-specific interference group (pLB-NRP-1/shRNA3) were significantly lower than that of the control group (P<0.05). Compared with the control group, the MCF-7 and SK-BR-3 cell-specific interference group (pLB-NRP-1/shRNA3) showed lower optical density values and higher apoptotic rates at 48, 72 and 96 h; these differences were statistically significant (P<0.05). EPI administration resulted in increased apoptosis in the MCF-7 and SK-BR-3 cell-specific interference groups compared with the control group (P<0.05). Lentiviral vectors encoding the human NRP-1 gene were constructed successfully and highly efficient NRP-1/shRNA interference sequences were selected. Furthermore, RNA interference (RNAi)-mediated NRP-1 silencing may induce proliferation suppression, apoptosis promotion, as well as enhanced sensitivity to chemotherapeutic agents.

Blocking of beta-2 adrenergic receptors hastens recovery from hypoglycemia-associated social withdrawal

Hypoglycemia is associated with a variety of adverse behaviors including fatigue, confusion and social withdrawal. While these clinical symptoms are well characterized, the mechanism of their cause is not understood. Here we investigated how insulin-induced hypoglycemia causes social withdrawal. Male 8-12-week-old C57BL/6J mice were injected intraperitoneally (IP) with or without and/or insulin, norepinephrine (NE) and epinephrine (Epi), terbutaline and butoxamine with subsequent measurement of blood glucose, social withdrawal and plasma catecholamines. Insulin generated (0.75h post-injection) significant hypoglycemia with blood glucose nadirs of 64+/-4 and 48+/-5mg/dl for 0.8 and 1.2units/kg of insulin, respectively. Insulin (0.8 or 1.2units/kg) caused near total social withdrawal at 0.75h with full recovery not occurring until 4h (0.8units/kg) or 8h (1.2units/kg) post-insulin injection. Insulin also caused a marked elevation in plasma catecholamines. Basal 12h fasting NE and Epi were 287+/-38 and 350+/-47pg/ml, respectively. Insulin at 0.8units/kg increased plasma NE and Epi to 994+/-73 and 1842+/-473pg/ml, respectively. Administration of exogenous NE or Epi caused social withdrawal similar in magnitude to insulin. Importantly, administration of the beta-2 adrenergic receptor agonist terbutaline also caused social withdrawal while administration of the beta-2 adrenergic receptor antagonist butoxamine blocked NE-induced social withdrawal. Finally, butoxamine blocked insulin-induced social withdrawal. These data demonstrate that hypoglycemia-associated social withdrawal is dependent on catecholamines via a beta-2 receptor-mediated pathway.

EPI vs IM administration of influenza virus vaccine

EPI vs IM administration of influenza virus vaccine

Insignificant effects of plasma catecholamines on dynamic heart rate regulation by the cardiac sympathetic nerve.

Although plasma catecholamines such as norepinephrine (NE) and epinephrine (Epi) increase during severe exercise, the effects of high levels of plasma catecholamines on dynamic heart rate (HR) regulation by the cardiac sympathetic nerve remains unknown. The aim of the present study was to examine the effects of plasma catecholamines on the transfer function from sympathetic nerve stimulation to HR. In anesthetized rabbits, we randomly stimulated the right cardiac sympathetic nerve according to a binary white noise signal while measuring HR. The effects of intravenous NE administration at 1 and 10 mugmiddotkg-1middoth-1 were examined in 6 rabbits. The effects of intravenous Epi administration at 1 and 10 mugmiddotkg-1middoth-1 were examined in different 6 rabbits. Although plasma NE increased 10 times as high as the baseline level during the NE administration at mugmiddotkg-1middoth-1 , dynamic gain of the transfer function was not changed significantly (7.1plusmn1.2, 6.9plusmn1.1, and 7.7plusmn1.1 beatsmiddotmin-1middotHz-1). Similarly, although plasma Epi increased 10 times as high as the baseline level during the Epi administration at 10 mugmiddotkg-1middoth-1, dynamic gain of the transfer function was not changed significantly (7.5plusmn0.8, 7.9plusmn0.8, and 7.6plusmn1.2 beatsmiddotmin-1middotHz-1). In conclusion, plasma catecholamines of physiologically-relevant high concentrations did not interfere with the dynamic HR regulation by the cardiac sympathetic nerve.

Epinephrine Fails to Hasten Hemodynamic Recovery in Fully Developed Canine Anaphylactic Shock

Background: Epinephrine (Epi) is the treatment of choice for reversing cardiovascular collapse in anaphylactic shock (AS). However, there are few data supporting its use in this condition, and most treatment guidelines have been anecdotally derived. In the present study, the time course of hemodynamic recovery from maximal hypotension was investigated in a canine model of AS in which Epi was administered by the intravenous (IV), subcutaneous (SQ) and intramuscular (IM) routes on different occasions. The findings obtained with Epi treatment were compared to those in a nontreatment study. Methods: Ragweed-sensitized dogs were examined in respective studies approximately 5 weeks apart in which Epi was administered by one of the above routes in a randomized design. Either Epi (0.01 mg/kg) or placebo was administered at maximal hypotension, and hemodynamics were followed for 3 h after shock. The animals were studied while ventilated and anesthetized. Mean arterial pressure (MAP), cardiac output, stroke volume (SV), pulmonary wedge pressure (Pwp) and plasma Epi concentrations were obtained at each measurement interval. Results: In the IV study, Epi produced a transient immediate increase in MAP, SV and Pwp as compared to the nontreatment study (144 vs. 52 mm Hg; 32 vs. 12 ml; 9 vs. 5 mm Hg; p < 0.01), but no differences were observed 15 min after shock. Hemodynamics were not different between Epi and no treatment at any intervals when Epi was given by the SQ and IM routes. AS compared with the placebo study, plasma Epi concentrations were higher in the IV and IM studies, but not in the SQ study. Conclusions: Although higher Epi concentrations were observed in the IM and IV studies, a sustained benefit in hemodynamic recovery was not observed in this anesthetized, ventilated canine model. In AS, when administered during maximum shock after mediators have already been released, a single IM, IV or SQ dose of Epi may have limited utility in the treatment of cardiovascular collapse. Earlier administration of Epi, before maximal hypotension occurs, may produce a more beneficial effect.